Process for separating petroleum emulsions



Patented July 5, 1938 PATENT orrice PROCESS FOR SEPARATING PETROLEUM EMULSIONS Ivor M. Colbeth, East Orange, N. J.,

The Baker Castor assignor to Oil Company, New York,

N. Y., a corporation of New Jersey No Drawing. Application July 6, 1936, Serial No. 89,133

10 Claims.

This application is a continuation in'part of my earlier applications Serial Numbers 567,753 filed October 8, 1931; 719,293 filed April 6, 1934 and 757,124 filed December 12. 1934.

This invention relates to the treatment of petroleum emulsions and petroleum containing emulsions of water and oil and foreign matter, commonly known as cut oil, wet oil, roily oil, emulsified oil, bottom settlings, basic sediment and B. 8., etc., for the purpose of eflecting the separation of the oil in the emulsion from the water, brine, or foreign matter, and rendering the oil suitable for commercial use.

Petroleum emulsions are of the water in oil type and are obtained from producing wells and from the bottom of oil storage tanks. These emulsions contain varying amounts of oil, water,

Y brine and/or foreign matter and are more or less stable, depending upon the conditions under which the emulsions are formed. Emulsions containing finely dispersed water, brine, or foreign matter are difilcult to break and are known as tight emulsions. Other emulsions not containing finely dispersed water, brine or foreign matter are known as loose" emulsions. Emulsions differ in composition and character, as different crude oils differ in viscosity and gravity and are produced under many different conditions. Adsorbed earthy matter, asphaltic matter, paraflinic matter, colloidal matter, water, brine, high gas pressure, naturally occurring in the production of crude oil cause the water and/or other foreign matter to emulsify with the oil. Methods employed for pumping or lifting the oil from the well also contribute to the formation of emulsions. All these factors create different kinds of emulsions. Some are tight and difllcult to treat, others are loose and not diflicult to treat in order to break the emulsion and separate the oil from the water and foreign matter.

I have discovered that petroleum emulsions can be broken and the water and/or foreign matter separated from the oil by means of substances or compounds derived or obtained by reaction between blown or oxidized fatty oils and reagents that will react with carboxylic organic acids to replace the hydroxyl of the carboxylic group, and it is an object of this invention to treat petroleum emulsions by said substances or compounds.

The term blown fatty oil as herein used includes not only the oxidized fatty oils but also the oxidized polymerized fatty oils obtained by simultaneous oxidation and polymerization, or

tended to include the products obtained when the fatty acids are used in place of the fatty oils. 5

The fatty oils are blown or oxidized fatty oils as described in my copendlng application, Ser. No. 59,089, filed January 14, 1936. These blown fatty oils contain a considerable amount of car boxylic acids, sometimes as high as 30% or more.

These blown fatty oils are reactive with the same class of reagents that react with carboxylic acids. The reactive reagents to be used are reagents that are capable of replacing hydroxyl groups of carboxyls, such as phosphorous penta- 15 chloride, sulphuryl chloride, thionyl chloride, monodiand tri-hydric alcohols, including methyl, ethyl, propyl, butyl, the glycols, mannitol, sorbitol and others. These reactivereagents combined with blown fatty oils and form compounds which are desirable for the treatment of petroleum emulsions.

The preferred blown fatty oil is blown castor oil, as it has thus far been found to be the most effective and satisfactory oil to use in the process. Other blown fatty oils, such as blown rape oil, corn oil, olive oil, or sardine oil, and the like, as described in my application, Ser. No. 59,089, filed January 14, 1936, may be used.

The above mentioned substances and compounds may be prepared by reacting blown fatty oils with the above mentioned reactive reagents until .a suilicient amount of the reagent has reacted with the carboxyls of the blown fatty oils to obtain compounds that will break petroleum emulsions. Usually about 25% or more of the equivalent weight of the reactive reagents is sufilcient. However, substantially complete reaction with the carboxyl content may be caused to take place with advantageous results. The 40 completion of the reaction may be determined by well known methods, as by titration for example.

A satisfactory compound or substance for treating petroleum emulsions may be prepared, for example, by intimately dissolving methyl alcohol with blown castor oil, adding about one percent of a mineral acid as a catalyst, refluxing the mixture until the carboxylic acids are esterii'led. The excess alcohol and mineral acid may or may not be removed. The mineral acid may be removed for example by adding an excess of precipitated chalk and filtering. The resulting compound or substance is ready for use.

Other reactive reagents which replace OH may be combined with the blown fatty oils by intimately mixing, with or without added heat, until the reaction has taken place to the desired degree.

The degree of reaction of the blown fatty oils may be varied. As petroleum emulsions differ in character the degree of reaction of the blown fatty oils suitable for particular types of petroleum emulsion may be determined by test.

These compounds or substances, which are the reacted blown fatty oils, may be mixed or combined with a viscosity reducing solvent in order to facilitate ease of handling, feeding, etc. Suitable viscosity reducing solvents may be selected from the solvents such as benzol, toluol, anthracene oil, xylene, propyl alcohol, pine oil, acetone,

petroleum solvents and the like.

In practicing the process a small amount of the reacted blown fatty oil may be fed into the emulsion by means of pressure lubricators or pumps of the types now in general use in the oil fields, for mixing with the emulsion. Approximately one part of the reacted blown fatty oil to amounts of the emulsion ranging from 500 parts of emulsion to 10,000 parts of emulsion may be used, depending upon the type and kind of emulsion being treated. The mass is allowed to stand until the emulsion breaks and separates into an upper layer of oil and a lower layer of water and foreign matter. The water and foreign matter are afterwards drawn off from the commercial oil. In most cases mixing the reacted blown fatty oil with the emulsion in the usual manner is sumcient to break and separate the emulsion in a period of time of one to six hours but in some cases where tight emulsions are being treated heat and/or agitation may be applied by the usual methods employed in the oil fields and a period of time of one to eighteen hours may be required to separate the emulsion.

I claim:

, l. A process for treating petroleum emulsions which comprises subjecting the emulsion to the action of a blown fatty oil, which has been reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls, capable of and in such proportions as to break the emulsion and allowing the mass to stand for a period of time suflicient'to effect a separation of the emulsion into an upper layer of oil and a lower layer of water and foreign matter, then withdrawing the water and foreign matter.

2. A process for treating petroleum containing oil, water and foreign matter emulsions which comprises subjecting the emulsion to the action of a blown fatty oil, which has been reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls, capable of and in such proportions as to break the emulsion and allowing the mass to stand for a period of time sufiicient to effect a separation of the emulsion into, an upper layer of oil and a lower layer of water and foreign matter, then withdrawing the water and foreign matter.

3;A'proc'ess for treating petroleum emulsions which comprises subjecting the emulsion to the action of a blown fatty oil, which has been reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls, capable of and in such proportions as to break the emulsion, heating and agitating the emulsion and allowing the mass to stand for a period of time suflicient to effect a separation of the emulsion into an upper layer of oil and a lower layer of water and foreign matter.

&. A process for treating petroleum emulsions which comprises subjecting the emulsion to the action of a blown fatty oil, which has been reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls and a viscosity reducing solvent, capable of and in such proportions as to break the emulsion and allowing the mass to stand for a period of time sufficient to effect a separation of the emulsion into an upper layer of oil and a lower layer of water and foreign matter, then withdrawing the water and foreign matter.

5. A process for treating petroleum emulsions which comprises subjecting the emulsion to the action of a blown fatty oil, which has been reacted with butyl alcohol, capable of and in such proportions as to break the emulsion and allowing the mass to stand for a period of time sufficient to effect a separation of the emulsion into-an upper layer of oil and a lower layer of water and foreign matter, then withdrawing the water and foreign matter. a

' 6. A process as defined in claim 2 further characterized in that the said blown fatty oil is a blown castor oil.

7. A process as defined in claim 2 further characterized in that the said blown fatty oil is a blown rape oil.

8. A process defined in claim 2 further characterized in that the said blown fatty oil is a blown corn oil.

9. An intimate mixture comprising a petroleum emulsion incorporated with a small percentage of a blown fatty oil that has been reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls.

10. A composition of matter comprising a major portion of a blown fatty oil reacted with an esterifying reagent which replaces hydroxyl groups of carboxyls and a minor portion of a viscosity reducing solvent.

IVOR M. COLBETH. 

